In what scenario would direct editing be essential in Solid Edge?

Direct editing is particularly essential when modifying imported models that do not have a parametric history. In scenarios where models are brought into Solid Edge from other CAD systems, it's common that they may lack the parametric data that would typically allow for easy modifications through feature history. Direct editing tools in Solid Edge provide a way to make changes to these geometric entities without the need for a parametric relationship.

This approach allows users to perform operations such as pushing, pulling, or twisting surfaces or solid bodies, which helps in fitting the imported geometry into the desired design context. It offers flexibility in adapting existing models to new requirements, especially when starting from non-native files that do not provide the same level of control as fully parametric designs.

In contrast, the other scenarios mentioned do not typically necessitate direct editing. For instance, designing from scratch often utilizes parametric features to establish relationships and constraints from the outset. Creating new parametric features involves establishing a design history that can be easily manipulated without the need for direct editing techniques. Lastly, generating assembly drawings does not require changes to the geometry itself, as it is primarily focused on documentation rather than modification of the models.